For example, various radio control models simulating airplanes, helicopters, cars, ships, robots and the like are known. In the case of causing a radio control model to fly or run, an operator operates an operation element such as an operation stick or the like provided in an operation-purpose radio device (transmitting device). The transmitting device generates an operation signal corresponding to the operation amount of the operation element and transmits the operation signal to the radio control model.
The radio control model is equipped with a receiving device configured to receive the operation signal and a controller (drive control device) configured to, based on the operation signal, control actuator devices (drive units) such as, e.g., servomotors or the like, for driving respective mechanisms of the radio control model.
The operation signal received by the receiving device from the transmitting device is delivered to the drive control device. The drive control device controls the drive units based on the operation signal. As a result, the operator can remotely control the radio control model.
Depending on the application of the radio control model, it may be required to have the radio control model fly or run a relatively wide range. For example, when obtaining a captured image of a site difficult to enter, such as a disaster site or the like, using a radio control model such as a helicopter or a multicopter equipped with a camera device, if the site is relatively wide, the flight range of the radio control model becomes extensive.
For the related prior art, reference is made to Japanese Patent Application Publication No. 2010-005121.
Since there is a limit to the range in which the radio control model can be operated with only one transmitting device, it is conceivable to adopt a method in which a plurality of operators (and transmitting devices) is disposed at a distance from each other so that each person operates a radio control model moved into the corresponding region.
However, according to the conventional receiving device, in a state in which the radio control model starts flying or running and moves away from an operator after the receiving device is linked to a certain transmitting device (communication ID) (so that the receiving device can receive an operation signal), it is difficult to cancel the link and change the link destination to another transmitting device (communication ID). Thus, it is difficult for the conventional receiving device to cope with the method in which the radio control model is operated by a plurality of persons as mentioned above.
The conventional receiving device may perform frequency hopping in the communication with the transmitting device side. In that case, if a plurality of transmitting devices sets (selects) a common communication ID, in the course of moving the radio control model, the signal reception level of a certain transmitting device (the transmitting device getting far away from the radio control model) tends to decrease and the signal reception level of another transmitter (the transmitting device getting close to the radio control model) tends to increase. As a result, there is a possibility that it becomes possible to receive an operation signal from another transmitting device after an operation signal from a certain transmitting device becomes unreceivable.
However, such a usage method is not the originally assumed usage method. It is uncertain whether it is possible to reliably receive the operation signal from another transmitting device. Even if the operation signal can be received from another transmitting device, it may take a relatively long time to search for a frequency band in which the radio control model can communicate with another transmitting device. In that case, the time in which the radio control model is in a non-operation state (so-called no-control state) becomes longer. In other words, there is a fear that the risk of crash or the like increases.